Restaurant spending increased by more than a third on Mondays, Tuesdays and Wednesdays across the UK during the Government's Eat Out to Help Out scheme compared to the month before, transaction data shows.
The initiative provided a 50% discount up to £10 between Mondays and Wednesdays on food and non-alcoholic drinks until August 31.
Data from Barclaycard Payments, which manages around 40% of all UK transactions, found that diners spent 34.2% more at restaurants and fast food outlets on the days subsidised by the Government than on the same days in July.
While the number of transactions also grew by 33.7%, the average value remained at around the same level.
The average restaurant spend increased by 6p from £11.85 in July to £11.91 in August despite the up-to-£10 per-head subsidy, indicating diners ordered more under the scheme.
Data shows that Wednesdays saw the biggest increase during the time of the scheme, with spending growing by 39.7%.
However, the total value of the transactions in restaurants and fast food outlets in August was down by 7% compared to August last year, with the total number of transactions down 11.6% for the same period.
Research by Barclaycard found 38% of Britons used the scheme, with more than half (52%) of those intentionally eating out on Mondays to Wednesdays to get their discount.
Implemented in an effort to attract more customers after falling footfall due to the pandemic, HMRC data for the week of August 23 showed £336 million had been claimed for 64 million diners.
A total of 87,000 claims have been made by restaurants and cafes signed up to the scheme, the Treasury said.
Several restaurants are continuing to offer the discount without government support, including Pizza Hut, Bill's and Pizza Pilgrims.
Barclaycard Payments CEO Rob Cameron said the scheme had a significant effect.
"It's clear that 'Eat Out to Help Out' had a positive impact on restaurant and fast food spend in August, resulting in many businesses choosing to extend the discounts into September, even without the Government incentive," he added.
"Consumer feedback has also been very encouraging, with almost one in five planning to continue dining out more often to support the industry and a similar number saying that they would return to restaurants that they would not have visited otherwise.
"Restaurants across the UK will be looking to maintain this boost in trade, especially with the Christmas period now in sight."
Some restaurateurs who have benefited from the drive here have vowed to continue offering discounts during September.
Michael Deane is one of those taking the financial hit to continue his own version of the scheme, shouldering the cost of cuts himself.
The Belfast chef said he would continue offering £10 off per person on Tuesdays and Wednesdays at some of his venues.
Home Restaurant in the city has also introduced its own scheme called #EatBelfastSupportBelfast.